Electric soldering iron



June 9, 1925.

C M. CHAPMAN ELECTRIC SOLDERING IRON Filed Nov. 19, 1924 Patented June 9, 1 925.

uurrsn STATES PATENT OFFICE.

CLARENCE M. CHAPMAN, TERRYVILLE,CONNECTICUT, ASSIGNOR TO THE 011;?-

MAN MACHINE COMPANY, OF'PLYMOUTH, CONNECTICUT, A CORPORATION OF CONNECTICUT.

Application filed November 19, 1924.

To all whom it may concern:

Be it known that I, CLARENCE M. CHAP- MAN, a citizen of the United States, resid .ing at Terryville, in the county of Litchtield and State of Connecticut, have invented a new and useful Improvement in Electric Soldering Irons, of which the following is a specification.

This invention relates to the type of electrically heated soldering implements Which have detachable copper points whereby points of the most convenient size for the particular work in hand can be quickly applied or a new point can be substituted should one in use become damaged.

The object of the invention is to so design, construct and connect the parts that the copper point will be most efliciently heated and the heating element suitably protected. I

To this end the heating element or electric resistance employed to raise the temperature of the point is located within and near the outer end of a metallic tube that extends into the hollow base of the point which point base is detachably screwed into the end of a sleeve that surrounds the tube about the heating element and contains a substantial amount of metal so as to conserve the heat generated by the heating ele ment and thus assist in keeping the point at the desired uniform temperature.

In the accompanying drawings Fig. 1 shows a side view of a soldering instrument which embodies the invention. Fig. 2 is a section on larger scale of the point end of the implement. Fig. 3 is a View of the handle with a portion cut in section.

The shank of the implement is a length of metallic tube 1 which extends into the handle 2 that may be made of wood or other heat non-conducting material. The tube is desirably perforated so as to reduce the conduction of heat toward the handle. This enables the shank to be shortened and adds to the convenience of handling the implement. The inner end of the tubular shank is corrugated or roughened and the shank end of the handle is slitted. After the tube has been driven into the handle the slitted end is bound by a spring wire ferrule 3. In the tube and extending to the outer end is the heating unit 4 which is an electrical resistance of common construction and to ELECTRIC SOLDERING IRON.

Serial No. 750,775.

which the circuit wires 5 the usual way. I

The exterior of the point end of the tube is threaded and screwed upon this thread is a metallic sleeve 6 having a thread in its interior near the point end and a knurled section 7 by means of which it may be readily grasped and turned. The sleeve contains a substantial amount of metal and extends toward the handle practically as far as the heating element. In the point end of the implement the sleeve has an interior thread and screwed into this is the base 8 of the copper point 9. The base of the point is chambered so that when it is screwed into the sleeve the end of the tubular shank and of the heating element therein extend into the chamber.

With this construction points of difierent size may be attached to the sleeve in order to accommodate the implement to various classes of work. As the bases of thepoints are hollow and the end of the heating eleare connected in ment extends for a distance into the opening the heating element is brought relatively near to the working point and heats it most efficiently. Although the heating element extends into the base of the point it is thoroughly protected both mechanically and from over-heating by the end of the tube in which it is contained. The sleeve forms a convenient means for the connection of the detachable points, and also being composed of a substantial body of metal it conserves heat radiated from the heating element and conducts it rapidly to the point, thus ensuring a practically uniform teniperature at the working end.

The invention claimed is:

1. An electrical soldering implement comprising a handle, a tubular shank extending from the handle, a heating element contained in the shank and extending to substantially the point end thereof, a metallic sleeve screwed upon the shank and surrounding the heating element, and a copper point having a hollow base screwed into the sleeve and surrounding the end of the tubular shank that extends from the handle and the heating element in said shank. 2. An electrical soldering implement comprising a handle, a tubular shank extending from the handle, said shank being perforated to increase the radiation of heat there- :troin, a heating element contained in the shank and extending to substantially the point end thereof a metallic sleeve screwed upon the shank and surrouinling the heating element and a copper point having a hollow base screwed into the sleeve and surlOUHCllHQ the end of the tubi'ilar shank that extends from the handle and the heatiugelement in said shank.

3. An electrical soldering implement comprising a handle having a slitted end, a tubular shank with a roughened end inserted into the slitted end of the handle, a coiled spring: Wire ferrule on the slitted end of the handle, a heating element contained in the shank and extending to'suhstantially the point end thereof, a metallic sleeve screwed upon the shank and surrounding the heating element, and a copper pointhaving a hollow base attached to the sleeve and surroimding the end ol? the shank and the heating element therein.

at. An electrical soldering iniplenient comprising a handle a tubular shank extending itroni the handle into the point, a heating element contained in the shank and extending to substantiall3 the point end thereof and into the tip, a metallic sleeve screwed upon the shank and surrounding the heating element, and a copper pointhaving a hollow base dctachably connected to the sleeve which is screwed upon the shank thatextends {P0111 the handle, said base of the tip surrounding the end of the shank and the end of the heatin element in the shank. CLARENCE M. CHAPWA'N. 

